Centrifugal separator



Dec. 26, 1950 i l.. s. KASSEL CENTRIFUGAL sEPARAToR Filed Sept. 13, 1946 Patented Dec. 26, 1950 UNITED STATES PATE NT OFFICE GENTRIFUGAL SEPARATOR 'Louis `S.'Kassel,Riverside, v'Ill., assigner to Universal Oil Products Company, Chicago, Ill., .a 'corporationofzDelaware .Applicationl September 13",LI9`46,S eial N o. 696,7 90

1vprovement comprises.r *connecting* a' "conduit to the body ,ofi'the .centrifugal separating apparatus `in :such va manner `as-to have anfauxiliary il'ow stream vsubstantially gprevent or 'eliminate any 'upward flow of gases :through the solid particlereturn line and thereby increase the eici'ency of* the centrifugal separating "apparatus,

kThe use of cyclone 'or centrifugal types of 'separating devices 'for `the vseparation and col- Tection of dust and iin'ely divided'sol'id particles an void art. The, general practice has ialways 'been 1to1 have-the centrifugal separators discharge "the coliectedparticles which have'b'een 'gathered' "from the outgoing gases, `into iafpotl Ior hopper 10 pairs the efciency of"this type Vof separator.

The improved Amethod and apparatusv of this' invention substantially eliminate this 'reverse gas `iiow `through the vsolid particle return line by vemploying an auxiliary ilow stream in communication with the body of rthe centrifugal 'type vof separator. ln one form of apparatus -and method of operation, Va jet pump or ejector is vused lin 'an auxiliary conduit connected with the dip leg from the solid "particle separator. VThe ejector Yand auxiliary flow stream passing through the 'conduit-operate to withdraw any upwardly flowinggas :from Within the solid `particle 'dip leg `and subsequently `discharge it to the interior'of the 'contact chamber. In another embodiment vof the from-which they maybe subsequently discarded 25 invention, :an injector, or other pressure type 'fof or withdrawn and returned to :the contacting discharging device, is Connected wiih'the bodyo'f chamber lfor reuse. 11n some contact processes, thecentrifugal separator inv a manner tomainsuch'as the riui'dized catalyst conversion'processes' fain :an increased 'pressure Within the 'Separation 'of the petroleum 4and chemical" industries,V vthe zone'and toth'ereby prevent any upward vilovv Aof v-iinely divided 'solid particles ofv catalyst which go gasthrough ythe lsolid `particle return line, from =are1employedare v'of considerable value and are lthe gas and Solid particle cnta'cting'zone. Vvretainedin the'system'by the -use-ofvarioustypes It is a "principal object of this invention 'to fof'scparating devices. VOutgoing:gasesA or vaporelimnateany upward gas flow through the dip m15 yreaction products tend to carry the -nely ileg'orsolidparticle return line from a centrifugal 'divided particles in entrainrnentfsuchthat prcd- 35v Vtype 'of 'separating device where the Separator 4uct streams must therefore be channeled through operates in combination with a closed contact `separating means. Centrifugal or` cyclone ltypes 'chamber and iS mounted at the upper end 0f :ofseparators are commonly `usedfin connection the latter'.

with the iiuidized catalytic lconversion processes It is another lobject of this invention to `proto prevent the solid materials from'passing out "40 `vide a lmore efilcient centrifugal Cyclone type withthe waste gases and tomaintain them w''thseparator by means of an auxiliary ilow fstream in certain contact zones. which alters and controls the normal gas ilowf and y Normally there vis an unavoidable pressure loss pressure drop through the separating device.

'through a centrifugal or cyclone 'type of separat- Suction fans, vejectors and the like vhave been ing' device such kthat the separated material ymust 45 lpreviously vused vwith separating devices by confbe'transferred from na zone of 'lower pressure to 'nectin'g lthem 't0 the cleansa's outletl suchthat '1a lnone lo! lhigher pressure. 'In 'such'cases it an increased velocityis obtained through the has been the usual practice to maintain ay column `separator. However, this type `of usage does `not yof separated solid particles 'in the return line leliminate the upward gas fiow through the-parf'from the cyclone separator hopper toV the in- 5o ticle return line and conversely tends toeg- `teriorof the Vcontacting zone, wherein the 'gas gravato this undesirable condition so thatV the fand' solid material'contact'is taking'plaoe, such :efficiency of the centrifugal separator is subthata'suiflcient'static head is obtained.to overstantially reducedv from that which is obtaincome the differential pressures jbe'tyveen; the two able. `'lhe'auxiliary iiow .stream employedin'this icones. This'staticheadovercomes `'thcunfauforo5 invention vconnects or communicates with 'the =of the contact chamber I.

vtion of the contact chamber.

`amount of entrained solid material.

body of the centrifugal type separator, rather than the clean gas outlet, and operates in a manner which will substantially prevent any upward gas flow through the solid particle outlet line, whereas the previously mentioned method of connection merely increases the undesirable condition.

The accompanying drawing and the following description thereof will serve to more fully explain various forms of the improved apparatus and the improved method of operation for effecting the ecient separation of solid particles from gaseous flow streams.

Figure 1 of the drawing is a diagrammatic elevational View of a chamber suitable for contacting gaseous mediums and finely divided solid par- 4 I through the outlet end of the ejector II. The flow through conduit I2 is capable of providing a jet pump action on the pipe I0, however the Venturi type ejector II provides a more eiiicient pump or suction action.

The ilow through the conduit I2 and the suction or vacuum provided by ejector I I should be maintained such that primarily gases only will be withdrawn from the standpipe ID but with a minor amount of solid particles entrained therein. Of course, the auxiliary ilow stream and the ejector II will necessarily provide a. certain amount of suction on the dip leg 9; however, this will act to increase the efficiency of the centrifugal separator 4 and positively prevent any up- Ward flow of gases thereto, through line 9, which ticles, with centrifugal type separation means I shown at the gas outlet and an ejector positioned at the upper end of a standpipe which in turn connects with the solid particle return line or dip leg from the separator. Y.

Figure 2 of the drawing is a partial elevational view of a contacting chamber and a centrifugal type separating device operating in connection therewith, with an ejector connecting directly to; ythe solid particle return line or dip leg.

Figure 3 of the drawing shows still another partial elevational view of a contact chamber with a centrifugal separating device mounted at the gas outlet from the chamber and with an auXili- .30

ary flow stream or injector mounted in the inlet to the separator such that an increased pressure may be provided within the body of the separat- .ing device to substantially eliminate an upward flow of gases within the solid particle dip leg.

Referring now to Figure 1 of the drawing, the chamber I may be any closed contact chamber suchas may be used in contacting uidized finely Adivided solid particles with a gaseous or vapor .stream Gases and nely divided solid particles may be charged to the chamber by way of inlet 2 while used solid particles may be withdrawn through outlet 3 and gaseous or vaporous reac- :tion products in turn withdrawn through separator 4 and the outlet line 5 at the upper end The separator 4 need not necessarily be mounted within the contact chamber- I, however, in gaseous and solid particle `,contact systems it has become common practice to maintain the separators within the contact chamber at a point above the dense fluidized phase which may be maintained in the lower por- In this drawing, the top level of the dense phase is indicated by vthe broken line 6, andthe Zone above this line comprises gaseous reaction products and a small 'I'he separator 4 has a tangential inlet l', a clean gas outlet 8 which in turn` connects with outlet line 5, and

a solid particle return line 9 which serves to return the removed solid particles to the dense :phase conta-ct Zone within the lower portion of at its upper end an ejector I I, of the Venturi type,

which in turn communicates with inlet line I2 having control valve I 3. An inert ilu-d or gaseous medium such as steam, flue gas or the like, is passed through line l2 and the ejector. I I and thereby provides suction on the standpipe I0,

such that any gases which pass upwardly through the lower end of standpipe I0 and which would normally enter the dip leg 9, may be withdrawn and `discharged into the interior of the chamber outlet line 5', and a solid particle return line 9.

In this form of the apparatus, an ejector I4 is positioned directly below the dip leg 9', with the latter connecting into the throat of the Venturi type of ejector I4. A conduit I5, having control valve I6, passes through the contact chamber I and connects with the ejector I4 such that allow stream of an inert medium may be passed therethrough and causea downward flow through discharge line I'I and -at the same time provide suction on the solid particle return line 9'. -This form of apparatus provides a somewhat more simple construction than that shown in Figure 1 and accomplishes the principal objective of preventing an upward gas ilow through the solid particle return line while at the same time providing a postive means for withdrawing solid particles from the lower portion of the separator .4 and for effecting an increased separating-eniciency in the latter.

Figure 3 of the drawing shows still another ymodification of the invention with a conduit extending into the inlet of a centrifugal type separator. The contact chamber I has acentrlfugal separator 4 mounted within its upper ,portion with the latter serving to'separate entrained, finely dividedV solid particles fromthe .outgoing gas stream such that the particles may be retainedy within the contact zone of the chamber I". Here again the separator 4 has a tangential inlet "I", a clean vgas outlet 8", which connects with outlet line 5, and a dip leg or solid particle return line 9". A conduit I8 having a valve I9 is extended into the chamber I" and into inlet 1 of the separator 4". A flow stream of inert material such as Steam, flue gas or .thev like, as previously noted, may thus be passed into the separator 4" through an injector or discharge nozzle 20, the Alatter being provided at the end of conduit i8 and extending intothe inlet 1". The auxiliary Vgaseous discharge from the injector 2U and conduit I8, provides van increased pressure within the body of the solid particle return line 9", which as previously noted, adversely aiects the eiciency of the centrifugal action within the body of the separator. The injector action of the auxiliary flow stream entering the cyclone separator 4" also tends to increase the velocity of the product gas and solid particle stream passing through the separator and provides an increased efiiciency of separation therein.

It is' not intended to limit this invention to the exact forms of centrifugal apparatus shown or to combining the auxiliary conduit and ow stream with a single stage of particle separation, for it is obvious that varying forms of apparatus and arrangement of parts may be employed. Also, as previously noted, the body of the separating device itself need not be mounted within the contact chamber as shown. With an exteriorly positioned separator, the general arrangement of the auxiliary conduit and ow stream with respect to the particle separator would be unchanged and will be substantially as shown and discussed with the solid particle return line and the ejector combination, as in Figures 1 and 2, discharging to the interior of the contact chamber. However, in the modication of Figure 3, the auxiliary conduit and now stream may be permitted to enter the inlet line to the particle separator without passing through the wall of chamber I.

I claim as my invention:

1. Apparatus of the type described comprising in combination a contact chamber, said chamber having inlet and outlet means and being arranged for contacting gases and finely divided solid particles, a centrifugal type separator at the gas outlet of said contact chamber, a solid particle return line passing from said separator to the interior of said contact chamber, a standpipe communicating at an intermediate point in the height thereof with the lower end of said solid particle return line, jet pumping means mounted across the Lipper end of said standpipe, a conduit connecting to Said pumping means with the latter adapted to receive and pass a now stream therethrough and operating to withdraw gas flowing upwardly through said solid particle return line while permitting gravity descent of solid particles through said return line and said standpipe to the interior from said Contact chamber.

2. The apparatus of claim 1 further cha-racterized in that said jet pumping means is a Venturi type of ejector.

LOUIS S. KASSEL.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,353,431 Sims Sept. 21, 1920 1,496,908 Schutz June 10, 1924 2,153,026 Rngius Apr. 4, 1939 2,214,658 Browning Sept. 10, 1940 2,289,970 Rowand et al July 14, 1942 2,378,607 Watts June 18, 1945 2,414,641 French Jan. 21, 1947 

1. APPARATUS OF THE TYPE DESCRIBED COMPRISING IN COMBINATION A CONTACE CHAMBER, SAID CHAMBER HAVING INLET AND OUTLET MEANS AND BEING ARRANGED FOR CONTACTING GASES AND FINELY DIVIDED SOLID PARTICLES, A CENTRIFUGAL TYPE SEPARATOR AT THE GAS OUTLET OF SAID CONTACT CHAMBER, A SOLID PARTICLE RETURN LINE PASSING FROM SAID SEPARATOR TO THE INTERIOR OF SAID CONTACT CHAMBER, A STANDPIPE COMMUNICATING AT AN INTERMEDIATE POINT IN THE HEIGHT THEREOF WITH THE LOWER END OF SAID SOLID PARTICLE RETURN LINE, JET PUMPING MEANS MOUNTED ACROSS THE UPPER END OF SAID STANDPIPE, A CONDUIT CONNECTING TO SAID PUMPING MEANS WITH THE LATTER ADAPTED TO RECEIVE AND PASS A FLOW STREAM THERETHROUGH AND OPERATING TO WITHDRAW GAS FLOWING UPWARDLY THROUGH SAID SOLID PARTICLE RETURN LINE WHILE PERMITTING GRAVITY DESCENT OF SOLID PARTICLES THROUGH SAID RETURN LINE AND SAID STANDPIPE TO THE INTERIOR FROM SAID CONTACT CHAMBER. 